University of Geneva, Bioenergetics and Microbiology Laboratory, CH-1254, Jussy-Geneva, Switzerland.
University Ibn Zohr, Faculty of Sciences, Department of Biology, BP/S-80 000, Agadir, Morocco.
Plant Physiol Biochem. 2016 Aug;105:102-108. doi: 10.1016/j.plaphy.2016.04.015. Epub 2016 Apr 9.
The objective of this study was to differentiate the heat tolerance in ten varieties of barley (Hordeum vulgare L.) originating from Morocco. Five modern varieties and five landraces (local varieties) collected at five different geographical localities in the south of Morocco were investigated in the present study. After two weeks of growth, detached leaves were short term exposure to various temperatures (25, 30, 35, 40, and 45 °C) for 10 min in the dark. Two chlorophyll a fluorescence parameters derived from chlorophyll a fluorescence transient (OKJIP) (performance index (PIABS) and relative variable fluorescence at the K-step (VK)) were analysed. Heat treatment had a significant effect on the PIABS and VK at 45 °C treatment and the analysis of variance for PIABS and VK is highly significant between all varieties. The slope of the relationship between logPIABS and VK named heat sensitivity index (HSI) was used to evaluate the thermotolerance of photosystem II (PSII) between the studied barley varieties. According to this approach, barley varieties were screened and ranked for improving heat tolerance. HSI was found to be a new indicator with regard to distinguishing heat tolerance of different barley cultivars.
本研究的目的是区分来自摩洛哥的 10 个大麦品种（Hordeum vulgare L.）的耐热性。本研究调查了来自摩洛哥南部五个不同地理位置的五个现代品种和五个地方品种（当地品种）。经过两周的生长，将离体叶片在黑暗中短时间暴露于不同温度（25、30、35、40 和 45°C）下 10 分钟。分析了来自叶绿素 a 荧光瞬变（OKJIP）的两个叶绿素 a 荧光参数（性能指数（PIABS）和 K 步的相对可变荧光（VK））。热处理对 45°C 处理时的 PIABS 和 VK 有显著影响，PIABS 和 VK 的方差分析在所有品种之间均高度显著。用命名为热敏感指数（HSI）的 logPIABS 和 VK 之间关系的斜率来评估所研究大麦品种之间 PSII 的耐热性。根据这种方法，对大麦品种进行了筛选和排名，以提高耐热性。HSI 是区分不同大麦品种耐热性的一个新指标。
